Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor  

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Got it all put together and printing. Extruder seems a lot smoother loading and unloading now. Went with the x-axis upgrades I posted and belt seems straight. Thanks.

Now if I could just get the y-axis idler to line up with the rest of the y-axis, things would be nice. Can't find any adjustment in that, holes must just be off.

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Rock on! That's great to hear. Thanks for the feedback, and happy printing!

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Got it all put together and printing. Extruder seems a lot smoother loading and unloading now. Went with the x-axis upgrades I posted and belt seems straight. Thanks.

Now if I could just get the y-axis idler to line up with the rest of the y-axis, things would be nice. Can't find any adjustment in that, holes must just be off.

Yeah, that's not likely to be the cause. Photos?

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Yeah, that's not likely to be the cause. Photos?

Don’t want to clog up this thread with it, maybe I will start a new one. Belt is centered on the motor side, I’ve tried adjusting what I can where the belt attaches. I used the original idler, it was the same as the new one. I switched to the adjustable one on thingiverse that lets you use a 16T. Belt is stuck hard against the right side if you are looking at the front of the printer. Belt is starting to squeak horribly loud.

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Do you have a version that supports this X-axis upgrade? Looks like there is a different x-carriage and back in the description to get belt alignment correct on the MK3S.

https://www.thingiverse.com/thing:2957916

Late to the party, but you can use the stock pulley with these x-ends if you use this idler carriage:
https://www.thingiverse.com/thing:3515627

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Mr. Butterworth,

I have your extended height N4 w/ MK3 sensor extruder installed on my machine and working like a champ. Thanks for putting this out there!

BTW I did tighten up the diameters around the bottom and top of the heat break, after reading that Prusa's R4 had opened them up. I had no trouble with fitment or assembly. Thanks for making the STEP files available. 🙂

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Yep - I had heard that too, but I haven't had any issue with the current R4 diameters. I cannot turn the extruder by hand once it's secured in place, which means it should be held securely.

Anyway, that's exactly why I included .STEP files! Glad they were useful to you. Enjoy!

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Took your N4 and did some work integrating Bunny Science gear drive into the extruder like I did for the Bear extruder.

The Bunny and Butterworth MK3S Geared Extruder. It's almost ready to be released in beta.

EDIT: Now up on Thingiverse https://www.thingiverse.com/thing:3571022

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

I recently printed the Butterworth parts and rebuilt my MK3S extruder. Went fine and I am having zero problems with it. A very nice design. Am looking with interest at the geared extruder, but I think I need to take a break from tweaks for a while. (I did put in a Moons' stepper and that worked well.)

Thanks to everyone who contributes to constant improvement!

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

I recently printed the Butterworth parts and rebuilt my MK3S extruder. Went fine and I am having zero problems with it. A very nice design. Am looking with interest at the geared extruder, but I think I need to take a break from tweaks for a while. (I did put in a Moons' stepper and that worked well.)

Thanks to everyone who contributes to constant improvement!

Hehe... it's a sickness. Welcome to the club of using your printer to do nothing but print improvements for it and not any actual things 😀

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Am looking with interest at the geared extruder, but I think I need to take a break from tweaks for a while.

Thanks for the feedback! And to be honest, I'm getting tired of tweaking things and extruders too! 😆

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

I have doen the same. I print more printer hacks and less projects.

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Hehe... it's a sickness. Welcome to the club of using your printer to do nothing but print improvements for it and not any actual things 😀

Indeed - when anyone asks me what I use a 3D printer for (the Prusa is my sixth) I always say "printing upgrades for the printer". That said, the Prusa is the first I've owned where I didn't feel I HAD to upgrade - I was getting fantastic prints right from the start.

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Hehe... it's a sickness. Welcome to the club of using your printer to do nothing but print improvements for it and not any actual things 😀

Indeed - when anyone asks me what I use a 3D printer for (the Prusa is my sixth) I always say "printing upgrades for the printer". That said, the Prusa is the first I've owned where I didn't feel I HAD to upgrade - I was getting fantastic prints right from the start.

At least in my case... it's because I have some big plans and I would prefer to understand my printer and have it be as perfect as possible before I commit to them.

At least, I'll keep telling myself that. 😆

Re: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Am just about to print off these for the indirect sensor. I'm planning on printing some parts in PETG and others in nylon/cf.

When I go to split the parts in slic3r (n4a-xt-indirectmk3fs-plate1-0-20mm.stl) the X carriage back also splits into the main object a bunch of vertical panels.

Let me see if I can post a pic.

Maybe I can fix it in the meantime by deleting all the other parts and doing an STL export but thought it might be worth bringing up in case there is an underlying cause in the model.

RE: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

I installed the XT version of this, and also installed a slightly longer PTFE tube cut in an angle.

I just printed Ninja Flex at 60mm/s!

I think i can go even faster, but I need to increase my extrusion multiplier, it was printing so fast the adjacent walls were not bonding to each other.

Thanks for the awesome work OP!

RE: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

I need to get on this... I've started having issues with Martin_au's variant; the filament sensor becomes unreliable as the bearing stops making contact with the filament once it has worn in a bit. Time to try this one. 

I know I will need to reprint all parts that involve the filament path (hot end cover, motor plate, hot end rear mount). Can I re-use the stock 3S X-backplate & tail, X-carriage, idler door, top cap, and fan shroud/mounting arm?

RE: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Hey there - sorry for the delayed response.  The switch to the new forum setup removed existing topic subscriptions it seems.

For the for the indirect Mk3 sensor (use the "N4A XT" version), you're mostly correct:

• Stock 3S x-backplate and tail can be reused.
• Stock 3S Idler door can be reused.
• Stock top cap (sensor cover) can be reused.
• Stock fan shroud and mounting arm can be reused.

Note:

• The stock X-Carriage can not be reused (the sensor connector orientation requires an additional cutout in the x-carriage).

Print the following two plates:

1. N4A Xt Indirectmk3Fs Plate1 0 20Mm.stl (print at 0.20mm layer height)
2. N4A Indirectmk3Fs Plate2 0 15Mm V1.stl (print at 0.15mm layer height)

Good luck, and happy printing!

RE: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

Posted by: Steve_AU

...

When I go to split the parts in slic3r (n4a-xt-indirectmk3fs-plate1-0-20mm.stl) the X carriage back also splits into the main object a bunch of vertical panels.

...

Maybe I can fix it in the meantime by deleting all the other parts and doing an STL export but thought it might be worth bringing up in case there is an underlying cause in the model.

Yeah, unfortunately that's what happens when that model is split - I have been thinking of uploading a .zip with all individual .stl files.

The cause is pretty simple: in the x-carriage, there are some very thin empty slots internal to the model.  These end up being voids that are supposed to force the slicer to put "external" perimeters there - aligned in certain directions, that can increase stiffness.  When the model is split, however, slic3r recognizes these as external surfaces, and fills them in on the wrong side, creating the vertical things you see there.

It's not a problem, they can be deleted and the model will still print and work just fine (they're probably overkill anyway).

You'll notice the difference if you slice the model and cut down into the middle layers of the carriage for both cases.

RE: Modified C1/R4 Mk3S parts - Better Filament Path, and a version for Mk3 Sensor

I've been running this design and unfortunately I get false runouts. I wonder if my bearing is either slightly undersized or the surface is not grippy enough to keep riding against the filament. 

I have a different bearing on which I have scuffed up the flange surface and added a thin heatshrink "tire" to improve the contact with the filament. Hopefully that will resolve the issue. But this design definitely makes cold pulls/loads much easier! (I sometimes do a cold load if I serviced something and am changing back to the same colour print... My start gcode does levelling at 140C so I don't want to bother heating up to load temp and then waiting for it to cool back down. If the previous cold pull was successful then the only result is missing a small bit of the purge line up front ;))